I got it from NAPA. Good thing I looked inside the box otherwise NAPA Assoc. gave me the temp sensor that I already purchased from AutoZone, the Duralast one. Then the Assoc. tells me that's what computer shows while I tell him, it can't be the one because of the diameter. Finally he dug deeper and gave me NAPA part number Echlin TS6685.
I can't get to drilling the hole and tapping it as it seems a little too much for my skills. There is always that first time though.